CORE COMPONENT B: Microscopy and Morphometrics The microscopy core facility has been reorganized under the leadership of a cell biologist and a pathologist to ensure that coverage of the diverse microscopy needs of the three projects are adequately maintained throughout the four years of this grant renewal and to direct the duties of the microscopist hired for this project. Microscopic techniques will be used to: 1) Evaluate the integrity of the diaphragm of SCID mice injected with the various cell lines (Project 2) using scanning electron microscopy; 2) Determine basement membrane invasion of SCID mouse organs and tissue by the different prostate cell lines using transmission electron microscopy; 3) Localize the expression of specific integrins, proteases, and extracellular matrix elements during tissue invasion in SCID mouse using confocal laser microscopy and immunogold probes at the TEM level (Projects 1, 2, & 3); 4) Perform confocal microscopy localization of matrilysin expression in tumors generated by subcutaneous and orthotopic injections in athymic nude mice by co-injection of LNCaP and prostate fibroblast cells (Project 3); 5) Perform video microscopy linear migration assay to evaluate the effects of substrate (laminin 5) on tumor cell migration (Project 1).